i´m new to cubase as well as to the CC 121. So far it works (using Win 8.1/64bit, Cubase 7.5)
But, i have three questions which i wasn´t able to solve so far:

1. Why can´t i put the Scub-Tool an a function-Button? I can assign it in the Menu, but when i try to use it, it has no effect. Programming other Tools an funcrion-Buttons work - not the Scrub-Tool

2. What´s the difference beween the Scrubbing-Mode in the Tools and the Scrub-Mode of the CC 121.
When i use the scrub mode from the Toolbar, i don´t hear my Plugins in this Channel, using the scrub-Mode of the CC 121, i hear the Plugins (they are not bypassed) Why?

3. Using the AI knob on my UAD Plugins the mouseover works (almost perfectly), trying to use the AI knob on Steinberg-Plugins, mouseover doesn´t. Why?